7 A steel sphere is released from a height of 9 m on the surface of the Moon. It is
known that the acceleration due to gravity
on the Moon is 1 the acceleration due
6
to gravity on the surface of the Earth.
Calculate the time taken by the sphere to
hit the surface of the Moon.
A 1.8 S
C 3.3 s
B 2.6 s
D 4.2 s

An  atom  (ours, not carroll's) consists of a positively charged  nucleus, surrounded by one or more negatively charged particles called  electrons. the positive charges equal the negative charges, so the atom has no overall charge; it is electrically neutral. most of an atom's mass is in its nucleus; the mass of an electron is only 1/1836 the mass of the lightest nucleus, that of hydrogen. although the nucleus is heavy, it is quite small compared with the overall size of an atom. the radius of a typical atom is around 0.1 to 0.25 nanometres (nm), whereas the radius of a nucleus is about 10-6  nm.  *  if an atom were enlarged to the size of the earth, its nucleus would be only 200 feet in diameter and could easily rest inside a small football stadium.read more on -